Combinatorial search for diagnostic agents: Lyme antibody H9724 as an example.
Two peptide libraries, Ac-MXXXXXBBRM and Ac-VXXXXXBBRM, were constructed on TentaGel solid support to search for ligands that bind tightly with the H9724 Lyme antibody. By using an on-bead ELISA, approximately 120 ligands were selected as candidates for further study. Matrix-assisted laser desorption ionization mass spectrometry analysis of the candidate ligands indicated a high rate of occurrence of certain amino acids at the randomized positions. On the basis of the initial screening results, a small library was designed and iteratively synthesized. Subsequent library screenings led to the identification of four peptides, Ac-PQEEGX-NH2 (X = R, K, A, D), that showed specific affinity to the antibody. This combination of solid-phase screening and iterative synthesis is an effective strategy for rapid identification of ligands that bind tightly with disease-specific antibodies and should be applicable, at least in principle, to other ligand-receptor systems. This combinatorial library approach can also be a useful tool for the discovery of novel diagnostic agents.
Tu
J
J
Department of Chemistry, Ohio State University, Columbus 43210, USA.
Yu
Z
Z
Chu
Y H
YH
D000906:Antibodies / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000737:chemistry / Q000276:immunology; D006801:Humans; D008024:Ligands; D008193:Lyme Disease / Q000175:diagnosis* / Q000276:immunology*; D019151:Peptide Library; D010455:Peptides / Q000138:chemical synthesis / Q000276:immunology; D017421:Sequence Analysis; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D000906:Antibodies; D000939:Epitopes; D008024:Ligands; D019151:Peptide Library; D010455:Peptides